Slack-thread controller for sewing-machines.



' 'No. 555,575. Patented Aug. 7, 1900.

m. v. PALMER. SLACK THREAD CONTROLLER FUR SEWING MACHINES.

(Application flied 055. 1, 1594.

(No Model.)

QM Own mm. 955M505 QRWMWKA 2 m "No. 655,575. Patented Aug. 7, I900.

I m. v. PALMER. SLACK THREAD CONTROLLER FC R SEWING MACHINES.

I (Application filed Oct. 1, 1894.)

(No Mqdel.)

2 Sheets-Sheet 2,

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NIT-ED STATES PATENT OFFICE.

MARO V. PALMER, OF WILLIMANTIC, CONNECTICUT, ASSIGNOR TO THE AMERICAN THREAD COMPANY, OF JERSEY CITY, NEW JERSEY, AND

NEW YORK, N. Y.

SLACK-TH READ CONTROLLER FOR SEWING-MACHINES.

SPECIFICATION forming part ofLetters Patent No. 655,575, dated August 7, 1900. Application filed October 1,1895 Serial No. 524,614. (No model.)

To all whom, it may concern:

Be it known'that I, MARO V. PALMER, a citizen of the United States, and a resident of Willimantic, in the county of Windham and State of Connecticut, have invented certain new and useful Improvements in Thread- Unwinders, of which the following is a full, clear, and exact description, whereby any one skilled in the art can make and use the same.

My invention relates to improvements in that class of devices known as thread-unwinders.

One object of my invention is to providea device of this class to support a mass of thread wound around a spool, bobbin, spindle, or the like and to so construct the same that the tension of the thread as it is withdrawn or unwound from the bobbin or spool may be perfectly controlled; anda further object is to provide means for varyingtho, tension upon the thread and also to provide means for antomaticallystopping the rotary movement of the bobbin to prevent unwinding and release of tension in case of the stopping of the machine which is supplied with thread.

To this end my invention consists in the combination and arrangement, in a threadunwinder, of the several parts as hereinafter described, and more particularly'pointed out in the claims.

Referring to the drawings, Figure 1 is a view in side elevation of a thread-unwinder embodying my invention, with parts cut away to show construction. Fig. 2 is a top or plan view of the same, with the bobbin removed. Fig. 3 is a detail view, in vertical central section, of a portion of the tension arm, the bobbin-support, the tension -controlling device, and their supports. Fig. 4 is a detail view, in central vertical, section, of the base'and the parts supported thereon in a plane at right angles to the plane of Fig.

' 3, the tension-arm with respect to the base being in'a position at right angles tothatshown in Fig. 8 and with the brake disengaged from the bobbin-support. Fig. 5 is a detail view, in central vertical section, of a portion of the device, showing a modified form of my invention. Fig. 6 is a detail'view,

the letter I) a standard secured to the base,

and the letter 0 an arm pivoted to the standard and having at its outer end a socket to 'receive the upper end of a bobbin d, support- I ing a mass of thread d, the lower end of the bobbin fitting a socket in the bobbin-support e, to which it may be secured in any ordinary manner. The base a is provided with a hub 61/, having a recess, within which is lo cated a bushing f. This bushing is secured against rotation in the hub to by means of the set-screw a projecting through the hub and with its innerendbinding upon the surface of the bushing. A sleeve g extends downward through a central opening in the bushing f, the lower end of the sleeve resting upon the bottom wall of the socket in the hub a, and a set-screwff projects through the bushing f, with its inner end thrusting against the outer surface of thesleeve g, this construction allowingthebushing to be rotated on the sleeve and cla'mped in any desired position for the purpose of controlling the tension ofthe spiral spring h, the lower end of which is secured to the bushing f, the upper end of the spring being secured to a hub on the lower end of the tension-arm c.

The spring h is preferably removably secured to the bushing f and tension-arm 2', as shown, the spring surrounding the sleeve g and resting upon the upper surface of the bushing f, the upper end of the spring thrusting against the tension-arm t.

' The tension-arm i is loosely mounted on the sleeve g, a screw t" projecting through the tension-arm, the inner end of the screw lying in a cam-slot g in the sleeve g. On the is thrown upward by the engagement of the screw 2" with the cam-slot g. It will be noted that the spring is so placed on the sleeve 9 that as the arm '6 is rotated to carry the brake-shoe away from the bobbin-support the springis contracted and in its recoil assists in raising the tension-arm 'i. A retaining-screw 7c is inserted through the wall of the sleeve g, the inner endof the screw resting in a peripheral slot in the stem 6 of the bobbin-support e. The screw is so placed in the sleeve as to allow the bobbin-support e a free rotation, but to prevent its accidental removal from the sleeve g in the application of the brake or otherwise, the effect of the action of the brake upon the bobbin depending to a certain degree upon the weight of the latter. In case the weight of the bobbin, however, should not be suflicient tostop its motion quick enough, the contact of the retaining-screw 7a with the lower surface of the peripheral slot in the stem 6 of the b'obbin-support e will provide additional means for stopping its rotation. In this instance the lower wall of the slot acts as a suppleupper side of the tension-arm '5 being in engagement with the cam-surface on the ring Z. In this latter construction the cam-ring serves the purpose of the cam-slot shown in the preceding figures of the drawings; but in this latter construction the cam-ring Z is employed to force the tension-arm 1 downward as the latter is rotated, and the recoil of the spring 71. is relied upon to carry the tension-arm upward in a position to cause the brake-shoe to engage the under side of the bobbin-support.

In the operation of the device a strand m from the mass of thread d projects through an opening in the upper end of the tensionarm '0', the base 0t being secured in such position as to cause the thread under the pull of the machine which it is supplying to swing the tension-arm ito one side and cause the brake-shoe i to be disengaged from the under side of the bobbin-support e. If for any reason a machine which is being supplied with thread suddenly stops, the arm 1' is immediately thrown to one side against the standard I), the brake-shoe i being caused to engage the under surface of the bobbin-support a and act as a brake to immediately stop the rotation of the bobbin and preserve the tension on the strand m of thread.

I have shown and described herein the spring as aiding in carrying the tension-arm upward to cause the brake-shoe to engage the under side of the bobbin-support, and this form of the invention is preferred, although it is obvious that any form of spring may be used to cause the tension-arm to rotate on its support and a cam be used to cause the tensionarm to move forward or away from the bobbin-support and yet embody the invention.

I do not desire to claim, broadly, herein a device wherein a brake-shoe is adapted to be carried into'and out of contact with a revoluble bobbin-support for the purpose of retarding its motion, one form of such device being shown in the prior patent to me, dated Febthe base, a tension-arm rotatively supported on the base and having a brake-shoe underlying the bobbin-support, and a cam in engagement with the tension-arm to cause it to move vertically,allsubstantially as described.

2. In combination in a thread-unwinder, a

base, a revoluble bobbin-support supported on the base, a tension-arm rotatively supported on the base and having a brake-shoe underlying-the bobbin-support, a cam in engagement with the tension-arm whereby the latter is forced toward or away. from the bobbin-support, and a spiral spring underlying the tension-arm and tending normally to force the arm upward and to rotate it, all substan tially as described.

3. In combination in a thread-unwinder, a base, a revoluble bobbin-support supported on the base, a sleeve secured to the base and supporting the bobbin-support,a tension-arm rotatively mounted on the sleeve, a cam-slot located in the sleeve and in engagement with a projection from the tension-arm, and a spring surrounding the sleeve and underly-- ing the tension-arm whereby the latter is normally rotated and moved upward, all substantially as described.

l. In combination in a thread-unwinder, a base, a bushing adapted to be secured to the base, a sleeve adj ustably secured to the bushing, a cam-slot located in the sleeve, a ten-' sion=arm rotatively mounted on the sleeve and having a projection engaging the camslot, and a spiral spring secured to the bush= ing and to the tension-arm and tending nor-' mally to rotate the latter and also force it upward, all substantially as described.

5. In combination in a thread-unwinder, a base, a socket in the base, a bushing adjustably secured in the socket,- a sleeve adjust ably secured in the bushing, a cam-slot lo-' cated in the sleeve, a tension-arm rotatively mounted on the sleeve and having a projec' tion engaging the cam-slot, and a spiral spring secured to the bushing and to the tension-arm arm gives vertical movement to the frictionbrake and thereby, by the braking and unbraking action of the friction-brake, controls the rotation of the bobbin holder or support.

7. In a thread-unwinder, in combination, a base, a revolnble bobbin-support mounted on the base, and having a stem with a shoulder, a stop cooperating-with said shoulder, a cam for moving the stem vertically whereby'the stop and shoulder are brought into engagement and a spring-actuated thread-guide connected with the cam.

8. In a thread-unwinder, in combination, a base, a swinging tension-arm underlying the bobbin-support and adapted in its swinging movement to make contact with the under surface of the bobbin-support, a thread-guide borne on the tension-arm, a cam in operative connection with the tension-arm to cause it to move vertically in its swinging movement,

a spring actuating the tension-arm in one direction, a stem for the bobbin-support, a pe ripheral groove located in the stem and a re taining-screw projecting into said groove.

9. A thread-unwinding apparatus comprisingin combination a base, a revoluble bobbin holder or support mounted on the base, a ten= sion-arm rotatively supported upon the base, a brake-shoe operated thereby, means arranged to be actuated by the tension-arm whereby horizontal oscillation of the tension-arm gives vertical movement to the brake-shoe and whereby the braking and unbraking action of the brake-shoe controls the rotation of the bobbin holder or support, substantially as described.

MARO V. PALMER.

Witnesses:

GEORGE W. MELONY, E. S. Boss. 

